The invention relates in general to munitions and, in particular, a gun launched, small caliber, autonomous, seeker assisted, guided projectile.
In the past, infantrymen engaged personnel targets with rifles that fired unguided projectiles. Firing on a moving target with a non-maneuvering projectile resulted in a low probability of hit, while the probability of hit for a target in defilade was zero. The introduction of shoulder fired, fragmenting grenades resulted in a higher probability of hit (by a fragment) against stationary targets. The probability of a hit against a moving target, or a target that went into defilade after projectile launch, remained quite low. There are several approaches currently used for these problems: (1) use a lead computing sight for moving targets, (2) use an automatic target tracker to follow the target while moving and mark its position in sight image space when the target went into defilade, and (3) use the output of an automatic target tracker to drive an off-boresight laser range finder to derive the range to the last observed position before the target moved into defilade, then use this information to derive aiming data for a sight.
The use of a lead computing sight requires a stabilized platform. Because a shoulder fired weapon is semi-stabilized at best, this potential solution is not satisfactory. The use of an automatic target tracker together with marking a target's last observed position in image space improves hit probability for an airburst fuzed grenade, but does not improve hit probability against a target which continues to move, and does not compensate for the effect of non-standard atmospheric conditions (primarily range and cross wind). Adding an off-boresight laser range finder to an automatic target tracker improves hit probability for both moving and move to defilade targets by improving the burst time accuracy for airburst fuzed grenades, but fails to compensate for aim error or for the effect of non-standard atmospheric conditions on flight time and deflection.
The present invention compensates for both aiming error and target motion after launch by locating the target in sequential images of the target area, while in flight, and using this information, plus information from an on-board guidance and control system, to alter the initial projectile trajectory. The influence of non-standard atmospheric conditions on the trajectory are compensated for by the same means, increasing the probability of hit. The present invention also increases the probability of hit against a moving target, or a target that goes into defilade after launch, by incorporating an adaptive, air burst fuze. Fuze function time is corrected from the launch setting by information from the imaging seeker and the guidance and control system.
The invention will be better understood, and further objects, features, and advantages thereof will become more apparent from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings.